Cylinder grinding machine



Sept. 5, 1950 c. A. FULMER CYLINDER GRINDING MACHINE 2 Sheets-Sheet 1 Filed Nov. 18, 1946 Sept. 5, 1950 c. A. FULMER CYLINDER GRINDING MACHINE 2 Sheets-Sheet 2.

Filed NOV. 18, 1946 bar/es /7 f'zz/mar muy?.

rlfatentec Sept. 5, 195() TED S TAT E S PATFE'N T OF Fl CE 2,521,21-0 CYLINDER GRINDiNG MACHINE Charles Almer, Fort Thomas, Ky.

Application November 18, 1'946fSerialNo. 710,561

Claims. (01.511-17-0) This linver'itin A'relates ito @grinding machines and islparticiilarl'y directed to "a machiriefor `effectif-ig v"special operations on closed end 'cyl-- indersofaircraft motors, 'or the like.

l'Ilfie closedend 'cylinder has been inlgeneral Vrise '-fo'r soine time Ain 'connection with internal combustn engines'for aircraft, or the like. The bores of :these-cylinders are lcrigrina'lly groundand -Fhoned to JvWithin minute tolerances fand during use-'arefs'uloje'lcted to intensive wearing 'actions by theiei'procation' of the motorpiston land .piston -rings therein. It is a :Well "recognized fact that fthe'fs'troke `of apiston and its associated Vrings iyithin fa cylinder unequally wear 'away the internal, "lateral 'surface of *thecylin'der bore until it =is '-s'lightly 'elliptical in 'transverse cross Y section, the greater elliptical diameter being inthe iplaneoffmov'ement of the associated piston c'on- Ynectingrod, or v `atrig'htangles to the axis Aof the motor crankshaft. 'A'lso the-piston rings :do: not traverse theentire lateral surface of 'the cylinder --bo'rebnthave fan upper liniit 'of motion removed ffrom the closed end 'of thecyli'n'der. The'por- Ytion of Athe internal rflateral surface of -a'worn cylinder lover "which Y the -piston vrings `travel has *a much greater Velliptical A"shape than 'the "fre- -mainder of ythe cylinderesurface therebyfor'r'ninga fridge-at 'the closed end thereon The length -of'l'saidfri'dge is vdetermined -by 'the -"distance fbetween the top of the cyI-ihderand the upper- "mos-t pointo'f travel of "the piston-rings.

In 'providing motors with new frin'gs "without a *cylinder i'egrin-dihg loperation, this ridge is objectionable Vin that new, unWoin 'rings run against itduringfthe Arst revolutions f the 'overhauled motorand cause `breakage crfdamage `to the top-ring and/or damage to the motor. Itis Atherefore theprimary object: of the :invention-to fprovide'a machine for grinding oia substantial- 'ly circular ridge from theelliptically shaped lateral falceof a Worn cylinderso Ythat theground sectionwill substantially conform `to the ellipti- `leal contour of the Worn section'of the face.

Another object lfof 'the invention is to Vprovide A=a Kmachine which makes `obsolete the previous "method oflgrinding off a cylinder'ridge by ahand --tool''operation Which-required a great ydealo'f time "v'vithlittleassurance-for accuracyexcept that of Athefsllill nof a trained operator.

A-'ifurther1 object of the-"invention is lto provide I'an limproved''grinding machine cf the character 'described Which "has" anov'el' combination and arrangements of parts, Iis thoroughly reliable `and 'mcien'tn' v'operation can be Vreadily adjusted 4and iet-fer grinding ope'rfatioris n'all sizes of cylin- -Ide'i"s, and isq'u'ickly and easily inserted into and withdrawn -'frorn the bores 'of l(said fcy-lin'ders.

'To'the foregoing'en'ds, generallyT stated, my inventionconsists ofith'e'fnovel ldevices 'and combilnatio'n ccf devices, vhereinafter described, 'illustrated in-the drawing, and 'defined in theappended claims.

vln the Aacccmpany'ing Vdrawing which shows fa piiefeiredfe'mbodimentof my invention, lkefchar- "'acters iridicat'eilik'e -partsthroughout `the -Several -vievvs wherein:

Fig. l is a fragmental, f'side elevational 'Vie-Wei my ridge grinding machine -in foperati-Ve position Within a closed fend cylinder.

Fig. 2 "is Aa cross sectional View taken on lline 122'fof Fig. 1.

Fig. 13 is a cross `sectional View taken on :line

eggs lfof Fig f1.

cooling fins l5 Aare formed on `the:externalf-lateral wallfof the fcylinder Aand said cylinder may also `have a `suitable motor block -boltingange i6 -at :its lopen yend. Frings of -a reciprocating piston traverse `thein- `In :operative .position @the ternal `'lateral surface if! of Jthe cylinder throughout a substantial I portion of its: intermediate surlface-and after a. period -lof use forms Va--circular yridge I3V thereon adjacent' the closed end. As

illustrated in Fig. 2f the YWorn internalsurface .-I'lv of Lthe -cylinder hasfa lslightly ellipticabshape in transverse cross section and 'it lis .the particustantially circular -ridge -f|8so that itcOniorms to the elliptically shaped worn Vinternalnsurface f of the-cylinder.

'Ehe-carriage lilly-is providedwith two spaced lateraIfmembeIs-IS and integrally -joinedfto- .gether at their-ends by cross-webs 2l and-22 and 'provided Withan intermedia-tecross Webf23. The Vguiding A4means for the Yrotatable carriage *within the-eylindei--comprises a pair oilcylinderfengagfinger/heels fe-e and 25J-25 rotatablyfixed' to suitable arms extending from the side members I9 and 2i? respectively. Each pair of wheels are disposed in spaced axial alignment on the axis which is parallel to the lateral face of the cylinder, and as moet clearly illustrated in Fig. 2, the respective axes of the pairs of wheels are tangentially space-d a transverse angular distance which should be not greater than 90.

The two pairs of wheels are urged into rolling contact with the worn lateral, surface of the cylinder by means oi a cylinder engaging pressure roller 26. This pressure roller is opposed to the pairs of wheels and has its axis lying on a bisector of the spaced pairs of wheels 24-24 and 25-25 which is perpendicular to the tangent extending between said wheels. As indicated in Figs. 1-5 the pressure roller is mounted for rotation on a lateral axle 21 parallel to the axes of the cylinder engaging wheels 24-24 and 25-25 and is supported between a pair of fork members 28 extending from a pneumatic piston 28. The piston is reciprocable and non-rotative within a pneumatic cylinder 30, integrally formed on the rear portion of the cross web 2l, the movement of said piston within the cylinder being limited by a, stop pin 3| threaded in the piston and radially movable in a slot 32 formed in the pneumatic cylinder wall. During operation of the machine air under pressure is supplied to the pneumatic cylinder by a exible line 33 tapped into a flexible main air pressure line 34 by a suitable T connection 35.

A suitable compressed air motor 36 is rockably mounted between the members I9 and 2i) of the carriage by suitable trunnions 3l and 33 which extend outwardly from a mounting bracket 39 surrounding the motor, said bracket being split at 4D and provided with suitable clamping nuts 4I (Fig. 3). The trunnions 3'I and 38 have conical seats in their end faces which receive conical pivot pins 42 and 43 threaded in the members I9 and respectively of the carriage and are secured therein by nuts 420 and 439 respectively. A grinding wheel 44 is fixed to a short drive shaft 45 of the motor, and as indicated in Fig. 2, the grinding wheel axis lies centrally between the pairs of cylinder engaging wheels 24-24 and -25 and is diametrically opposed to the pressure roller 26.

The shaft of the motor is driven by compressed air introduced to the motor through the T connection 35. The exhaust ports 45 for the motor are directed toward the periphery of the grinding wheel as is clearly indicated in Fig. 1, the exhaust air being adapted to circulate about the wheel and carry off particles produced by the grinding operation through the cylinder ports I3 and I4. The main compressed air line 34 communicates with an air passageway 41 formed in the outer end of a handle 48 by a connection 49, said handle being threaded to the cross web 22 of the carriage and locked thereto by a set nut 50.

A depth stop is provided for the carriage to dispose the working face of the grinding wheel in transverse alignment with the circular ridge I8 to be ground from the cylinder, said stop being generally indicated by the reference numeral 5I and comprising a mushroom headed screw 52 threaded in a lug 53 and xed therein by a set nut 54 (Fig. 4). The lug is provided with a pair of oppositely disposed and transversely extending mounting flanges 55 each having a vertical slot 56 formed therethrough, for receiving a countersunk set screw 5'! which threadedly engages one of a plurality of internally threaded drical 4 bores 58 formed in the forward end 59 of the cross web 2 I. It will therefore be noted that the stop may be laterally and transversely extended for operation on various types of cylinders having diierent bore sizes.

An adjustable means is provided between the rockable motor and the carriage for adjusting the radial position of the grinding wheel, said means comprising a pair of spaced arms 60 depending from the motor mounting bracket 39 and embracing the head 6I of a boss 62. The head is pivoted between the arms 60 by a pin 63 secured therebetween and riding in a transverse slot 54 formed in the head 5I. The boss 62 has a cylinportion provided with an internally threaded bore 65 for receiving the threaded end of an elongated adjusting screw 66. The, boss is slidably supported within a close fitting bore 61 formed laterally through the cross web 23 of the carriage. As illustrated in Fig. 5, the adjusting screw 66 is rotatably mounted against axial movement in the cross web 22 by means of a thrust bearing 68 secured within an annular recess 69 in the web. The screw has an annular shoulder 'IEJ formed thereon which abuts the inner race of the bearing 58, said inner race being secured to the shaft by a nut 'Il threaded to said shaft and tightened against the race in the direction of said shoulder. The outer race is clamped against a shoulder 'I2 formed in the recess 69 by a ring 'I3 secured on the web 22 by screws 14. A suitable dial is frictionally secured to the outer end 'I6 of the shaft 66 by an expansion spring 'II which encircles the shaft portion 'I6 and urges the dial against a collar 'I8 iixed to the shaft. The shaft is turned by a suitable hand wheel 19.

A modified form of pressure roller mounting for my device is illustrated in Fig. 6 wherein a piston 8U is disposed within the cylinder 8| extending radially from the carriage 2|. The piston is urged outwardly by a compression spring 82 the limits of motion thereof being determined by the pin and slot arrangement 83 as in the preferred form of roller mounting illustrated in Figs. 1-5 inclusive. This modified roller mounting permits the use of an electric motor with my device instead of the pneumatic motor disclosed herein or it may be used in conjunction with a pneumatic motor, if desired.

In operation, the working face of the grinding Wheel is first dressed on any suitable dressing mechanism to an angle which will leave the iinished ground surface parallel to and flush with the lateral surface of the worn part of the cylinder. The grinding device is then inserted in the cylinder to be ground with the motor inoperative and the grinding wheel is fed out radially by the hand wheel 'I9 until the wheel contacts the worn surface of the cylinder. In said position the dial 'I5 is rotated on shaft 'I6 into a Zero position with respect to calibrations formed either on the dial or on the surface of the carriage surrounding said dial. The grinding wheel is then backed'of a suitable distance from its finishing position by rotating the hand Wheel 19, thereby rocking the motor on its trunnions and moving the grinding wheel a certain radial distance inwardly. The depth stop 5I is thereafter adjusted laterally and transversely for the particular cylinder to be ground and thereafter the entire machine is inserted through the open end of the cylinder until the stop 5I is against the cylinder head I2. Compressed air is then introduced through the main line 34 which simultaneously vexpands the pneumatic cylinder for the pressure roller 25 and furnishes motive power for the grinding wheel. Upon introduction of air under pressure into the pneumatic cylinder 3l), the pressure wheel 26 will expand outwardly and positively urge the two pairs yof wheels 2li-24 Yand 25e- '25 against the worn iateral surface fof the cylinder. The pneumatic motor is thereafter rocked on its tru-unions by rotation 4of the hand wheel 19 to feed the grinding wheel against the circular ridge I8 and the entire carriage is thereafter rotated by the handle A8 until a certain amount of stock has been ground from the entire circumference of the ridge. 'I'he hand wheel is again rotated to feed the grinding wheel a further distance into the Work and again the handle 48 is rotated and said cycle of operations is continued until the indicator l5, by registering Zero, shows that the proper amount of stock has been ground from the ridge.

What is claimed is:

1. In a cylinder grinding machine of the character described the combination of a rotatable carriage, spaced wheels fixed to the carriage and adapted to run on the internal lateral surface of the cylinder, a pressure roller opposed to the spaced wheels, a radially expansible roller mounting on the carriage, a motor having a short shaft, a grinding wheel fixed to the shaft, a transversely positioned trunnion means for mounting the motor to the carriage, and a means between the carriage and the motor for adjusting the radial position of the grinding wheel.

2. In a cylinder grinding machine of the character described the combination of a carriage rotatable within the cylinder, spaced wheels fixed to the carriage and adapted to run in a path around the internal, lateral surface of the cylinder, a pressur-e roller opposed to the spaced wheels, a radially expansible roller mounting on the carriage, and a motor driven grinding Wheel mounted on the carriage for radial feeding movement with respect to the cylinder.

3. In a cylinder grinding machine of the character described the combination of a rotatable carriage, spaced wheels fixed to the carriage and adapted to run in a path on the internal, lateral surface of the cylinder, a cylinder engaging pressure roller opposed to the spaced wheels, a radially expansible roller mounting on the carriage, a motor having a short shaft extending laterally from the carriage end, a grinding Wheel fixed to the shaft and positioned intermediate the lateral extensions of the wheels and in a position opposed to that of the pressure roller, a transverse trunnion for mounting the motor n the carriage, and adjustable means between the carriage and the motor for radially feeding the grinding wheel against the surface of the cylinder.

4. In a cylinder grinding machine of the character described the combination of a carriage rotatable within the cylinder, a pairl of cylinder engaging wheels fixed to the carriage and disposed in spaced axial alignment on an axis parallel to the lateral face of the cylinder, a second pair of cylinder engaging wheels fixed to the carriage and positioned in spaced, axial alignment with their common axis parallel to the lateral face of the cylinder, said second pair of wheels being tangentially spaced from said first pair of wheels with respect to the cylinder surface, a cylinder engaging pressure roller opposed to the pairs of wheels, a radially expansible roller mounting on the carriage, and a motor driven ,6 grinding wheel mounted on the carriage for urging the roller against the cylinder surface.

'5. In -a cylinder grinding machine of the character described the combination of a carriage rotatable within the cylinder, wheels fixed to the carriage and adapted to run in circular paths around the internal, lateral surface of the cylinder, said wheels being angularly spaced with respect to a transverse plane of the cylinder, a cylinder engaging pressure roller opposed to the wheels and having its axis lying on a diameter of the cylinder bisecting the angle between said wheels, a radi-ally expansible roller mounting on the car-riage, a motor driven grinding wheel diametrically opposed 'to the roller, trunnion means for mounting the grinding wheel on the carriage, and means between the trunnion means and the carriage for adjusting the radial position of the grinding lwheel with respect to the cylinder surface.

6. In `a cylinder grinding machine of the character described the combination of a carriage rotatable within the cylinder, a guiding means for the carriage within the cylinder comprising a pair of cylinder engaging wheels mounted on the carriage and disposed in spaced axial alignment on an axis parallel to the lateral face of the cylinder, a second pair of cylinder engaging wheels mounted on the carriage and relatively positioned in spaced axial alignment with their axes parallel to the said lateral face of the cylinder, the said second pair of wheels being tangentially spaced from said first pair of wheels, a cylinder engaging pressure roller opposed to the pairs of wheels and having its axis lying on a bisector of the spaced wheels perpendicular to the tangent extending lbetween the said wheels, a radially expansible roller mounting on the carriage, a motor driven grinding wheel diametrically opposed to the roller, trunnion means for mounting the grinding wheel on the carriage, and means between the trunnion means and the carriage for adjusting the radial position of the grinding wheel with respect to the cylinder surface.

7. In a cylinder grinding machine of the character described the combination of a rotatable carriage, spaced Wheels fixed to the carriage and adapted to run on the lateral surface of the cylinder, a cylinder engaging pressure roller opposed to the spaced wheels, a pneumatic cylinder for mounting the roller on the carriage for radial feed and return movement, a pneumatic motor having a short shaft extending laterally from the carriage end, a grinding wheel fixed to the shaft and positioned intermediate the lateral extensions of the wheel axes and diametrically opposed to the pressure roller position, air dis-charge outlets on the motor adapted to direct air laterally around the grinding wheel, a common source of compressed air for the motor and pneumatic cylinder, a transverse trunnion for mounting the motor on the carriage, and adjustable means between the carriage and the motor for radially feeding the grinding Wheel against the surface of the cylinder.

S. In a cylinder grinding machine of the character described the combination of a rotatable carriage, spaced Wheels fixed to the carriage and adapted to run on the lateral surface of the cylinder, a cylinder engaging pressure roller opposed to the spaced wheels, a pneumatic cylinder for mounting the roller on the carriage, a pneumatic motor rockably mounted on the carriage, a grinding wheel driven by the motor, air

outlets on the motor directed toward the grinding wheels, a common source of compressed air for the motor and pneumatic cylinder, and means .between the carriage and motor for adjusting the radial position of the grinding wheel with respect to the cylinder surface.

9. In a ridge grinding machine for closed end cylinders the combination of a rotatable carriage, spaced wheels xed to the carriage and adapted to run on the internal lateral surface of the cylinder, a pressure roller opposed to the position of the spaced wheels, a radially expansible roller mounting on the carriage, a motor driven grinding wheel mounted on the carriage for radial adjustment and having a Working surface greater than the width of the ridge, and a depth stop laterally and transversely adjustable on the carriage and adapted to engage the closed end of the cylinder when the carriage is rotated within the cylinder.

10. In a cylinder grinding machine for grinding away the round ridge formed on the internal lateral surface of a worn cylinder for an internal combustion engine, the combination of a carriage adapted for bodily insertion within the cylinder, a xed wheel mounted on the carriage and adapted for rolling engagement around the said lateral surface, a transversely movable pressure roller mounted on the carriage in opposition to the fixed wheel and adapted for rolling engagement around the said lateral surface, a grinding wheel mounted on the carriage for transverse feeding movement against the ridge, and means fixed to the carriage and adapted for extension beyond the cylinder for rotating the carriage.

CHARLES A. FULMER.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS 0 Number Name Date 1,656,388 Nielsen Jan. 17, 1928 1,799,109 Lyne Mar. 31, 1931 

